[2.1.9]Performance problem: Construction manager consumes ~100 ms/tick

[Okalion]

Version: 2.1.9
Mods: None (vanilla + Space Age)

The game gradually developed a severe UPS degradation.

Initially, the slowdown occurred only occasionally (or at regular intervals) and lasted for a short time before recovering. Over time, both the frequency and the duration of these slowdowns increased until the game eventually remained at approximately 8 UPS almost continuously.

The performance debug overlay shows:

Construction manager: ~97–114 ms/tick
Entity update: ~2 ms/tick
Logistic manager: ~0.13 ms/tick
Electric network: ~0.4 ms/tick

Almost all update time is spent inside Construction manager.

Entity update, transport lines, electric network, fluid system, trains, and logistic manager all appear to have normal CPU usage.

Using the debug editor, I removed all entities from Navius surface, and the performance returned to normal.

[boskid]

From a quick check it looks like this situation is caused by the cargo landing pad on Gleba and items overflow onto ground, more specifically that there is a pile of 87k item-on-ground entities at the position of cargo landing pad, each time robot checks to pickup one of them there is a tiny entity search performed and it visits all other 87k items on ground.

[Rseding91]

Do you know how Gleba got into this state? (with all the items on the ground)

[Okalion]

I repeatedly dropped resources manually from the space platform.
And I overlooked the state of the Gleba surface.
My "mottainai" spirit made me do it, sorry.